Chemistry math question. Ratios of solutions

Question

How much of a solution that is 30% alcohol must be added to 55 liters of a solution that is 60% alcohol to obtain a solution that is 40% alcohol?

Answer 1

If we add something (x) to 55 we get 55 +x.

 

55 + x = (55 +x)     Now put in the percentages

0.6(55) + 0.3x = 0.4(55 + x)

33 + 0.3x = 22 + 0.4x

11 = 0.1x

110 = x

 

One hundred ten liters of the 30% solution must be added.